Not applicable.
Not applicable.
1. Field of Invention
The invention relates to the field of electric power transmission and distribution, more particularly to electric power transmission lines having retunable elements for reducing harmful EMF related emissions.
2. Background of the Invention
A transmission line can be considered to be any structure that can transfer electromagnetic energy between two points. There are many different types of transmission lines including coaxial, strip line, parallel wire and parallel plate. Regarding power line transmission of energy, parallel wire is generally used.
Numerous studies have been conducted on the relationship between power line EMF and serious disease. The official U.S. government view is that EMF may cause cancer, especially in children. There have also been suggestions that EMF may lead to miscarriages and other harmful effects.
Countries other than the U.S. have also been concerned with EMF originating from power lines. For example, because of health concerns, Spain, Norway, Sweden, the UK and Australia now prohibit the construction of power lines within 300 feet of homes.
One proposed method for avoiding or at least reducing potentially harmful EMF exposure is by burying power lines. However, some have argued that this would not significantly reduce the harmful EMF radiated by power lines. Even if effective, burying of power lines is very expensive and is not possible in certain regions, such as regions prone to flooding.
A current conducting part of an electrical power transmission line and electrical power transmission line for reducing harmful EMF related emissions includes a plurality of interconnected individual conducting sections, and a plurality of conducting section connectors disposed between the conducting sections. At least one of the section connectors include at least one retunable inductor element connected in series between respective ones of the conducting sections. The retunable inductors can provide random variation in magnetic permeability (xcexc) on adjacent current conducting sections. Such an arrangement can result in averaging of at least one of the first, second and third directional derivatives of vector potential of electromagnetic waves traveling in adjacent conducting sections. Averaging of respective derivatives renders the same undefined.
Averaging at least one of at least one of the first, second and third directional derivatives of vector potential of electromagnetic waves traveling current conducting sections can eliminate or at least substantially reduce operation in the concurrence of mode condition that can exist in the power lines. During the concurrence of mode condition, self-sustained oscillations of the power lines can occur, resulting in excitation of chemical bonds in the power line material and emission of harmful EMF. Harmful EMF can also excite molecules in materials outside power supply lines and is emitted due to pulses of energy which transfer energy between respective oscillation modes which occurs during operation in the concurrence of mode condition.
Harmful EMF related emissions from power lines have been determined to occur primarily during periods in which the concurrence of mode conditions condition exists in the power lines. As a result of eliminating or substantially reducing the occurrence of concurrence of mode operation of power lines, harmful EMF related emissions from power lines can be reduced.
The transmission line can include at least one random number generator for controlling variation of the retunable inductances. As used herein, the term xe2x80x9crandom numbersxe2x80x9d and xe2x80x9crandom number generatorsxe2x80x9d includes pseudo-random numbers and pseudo-random number generators, respectively.
A structure for calculating values of the retunable inductors can also be provided. Values calculated and used for varying inductances are preferably comparable to the inductance of the section of the wire (cable) enclosed between the two tunable inductors between the retunable inductors and a load.
The transmission line can also include a structure for varying the retunable inductors. The structure for varying can be an electrical, mechanical or electromechanical device.
A method of transmitting electric power with reduced harmful EMF emissions includes the steps of providing a plurality of interconnected individual current conducting wire sections and a conducting section connector disposed between the conducting sections. At least one of the section connectors includes at least one retunable inductance connected in series between respective ones of the conducting sections. The retunable inductance are capable of causing random variation in magnetic permeability (xcexc) on adjacent ones of the conducting sections, wherein at least one of first, second and third directional derivatives of vector potential of electromagnetic waves traveling in adjacent conducting section can be averaged, thereby becoming undefined.
The method includes the step of randomly varying the effective magnetic permeability (xcexc) on at least one of the conducting sections. The random variation can result in averaging at least one of the first, second and third directional derivatives of vector potential of electromagnetic waves traveling in adjacent conducting sections. This averaging can eliminate or at least substantially reduce operation in the concurrence of mode condition that can exist in the power lines.
The random variation can be produced by randomly varying values of the retunable inductances. The method can include the step of controlling the random variation. Random variation of inductances can be controlled by at least one random number generator.